October 6, 2020 Why Does Your Gun Drill Wear Out Particularly Fast?

The CNC gun drill center controller is designed to control each head individually through the dual system control.

As the requirements for mechanized production continue to increase, the tools manufactured and manufactured are updated, and the drilling standards for various metals allow the design of gun drills to be updated continuously. Why do some gun drills last for a long time, but the drill bit in your hand wears out quickly?

Let’s first understand the working principle of the gun drill. This tool, named after the earliest deep hole processing of the gun barrel, belongs to the external chip removal deep hole drill. When in use, the cutting fluid will enter from the middle of the drill rod, erupt into the cutting area through the small hole of the drill head, and then discharge the chips from the V-shaped groove of the drill bit. This drill is suitable for processing deep holes with a hole diameter of 2-20 mm and a ratio of hole depth to a hole diameter higher than 100.

Deep hole machining is a difficult point in mechanical machining, and gun drills play an important role here. The same gun drill, different materials processed, will directly affect the service life of the tool. Choose appropriate processing technology and parameters for different materials, including but not limited to: speed, feed rate, cooling oil pressure. Secondly, processing equipment, processing mode, cooling mode all affect the processing life and processing quality of the gun drill influential.

So when choosing processing equipment, you can prioritize gun-drills individual machines or processing centers with in-cooling. In the choice of processing mode, parallel processing is more advantageous than vertical processing, and for cooling, you can prioritize high-pressure oil cooling. Finally, do not forget to check whether the accuracy of the gun drill’s pilot hole in your hand meets the requirements of the processing material.

Excluding the impact of various tool choices, improper use will also make your gun drill wear out particularly quickly.

Such as:

When the difference between the axis of rotation of the drill sleeve and the drill bit is too significant, the gun drill usually fails, such as the impact of the drill tip, the weak carbide tip cannot withstand the bending caused by the different centers caused by stress The drill bit broken;

When the gap between the drill sleeve and the drill bit is too large, the gun drill’s side edge will cut off a large amount of material, and excessive cutting force will also cause the side edge to break;

When the coolant supply is insufficient, the wear of the gun drill will also be accelerated. A large amount of cutting accumulates in the chip flute. These squeezed chips form a blockage, allowing excessive torque to act on the gun drill and accelerate its failure.

To reduce the wear of the gun drill, you can refer to the data recommended by the manufacturer, including the pressure and flow rate of the high-pressure cooling system, and the cutting oil should also use special deep hole cutting oil containing extreme pressure additives.  During the drilling process, there should be a guide sleeve or guide hole guide, and when the size of the inner hole of the guide sleeve is larger than the gun drill size 0.02mm, you should replace it in time.

To ensure the gun drill’s processing performance, you need to regularly check the wear of the gun drill, and accurately regrind them with the help of the gun drill grinder and the sharpening fixture.

When the amount of wear reaches the following dimensions, your gun drill should regrind: the flank wear of the drill bit with a diameter ≤15mm (0.591 inches) reaches 0.2-0.4mm (0.0079-0.0158 inch); The flank wear of the drill bit with a diameter >15mm, reaches 0.4-0.6mm (0.0158-0.0236 inches).

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